1. Field of the Invention
The present invention generally relates to fingerprint verification, and more particularly to an iterative matching method and system for partial fingerprint verification.
2. Description of Related Art
Fingerprints have been the most widely used biometrics applied as a form of identification and access control. Fingerprint verification has been gradually used in electronic devices, particularly handheld electronic devices (e.g., mobile phones or tablet personal computers) to replace password verification in a more convenient and safer manner.
A fingerprint is characterized by ridges and valleys, of which a pattern is uniquely made to each person. Major features of a fingerprint are minutiae that include, for example, ridge endings and ridge bifurcations. Fingerprint verification involves two stages: (1) enrolment and (2) matching. In the enrolment stage, enrollee fingerprints are acquired and stored in a database. In the matching stage, a claimant fingerprint is compared with the enrollee fingerprint.
Some fingerprint sensors, particularly of handheld electronic devices, have a size smaller than the magnitude of a typical fingerprint. Those fingerprint sensors, therefore, can at most detect partial information about the fingerprint. Accordingly, performance of fingerprint verification using the small-size fingerprint sensors would degrade greatly, compared to that using full-size fingerprint sensors.
Features (or minutiae), instead of a full fingerprint pattern, are commonly involved in fingerprint verification. However, due to deviation of corresponding features, relation of translation and rotation of the corresponding features usually causes feature mismatch, therefore decreasing performance, for example, measured in terms of genuine acceptance rate (GAR).
For the reason that conventional fingerprint verification could not be effectively performed based on a partial fingerprint input, a need has arisen to propose a novel method for partial fingerprint verification with enhanced effectiveness.